# Definition:Planck's Constant

## Definition

Planck's constant is the physical constant $h$ whose value is defined as:

$h = 6 \cdotp 62607 \, 015 \times 10^{-34} \, \mathrm J \, \mathrm s$

where the units $\mathrm J \, \mathrm s$ are joule seconds.

Physical quantities with the same dimension include angular momentum and action.

## Also known as

Planck's constant is also seen referred to as the Planck constant.

## Source of Name

This entry was named for Max Karl Ernst Ludwig Planck.